Why cheat downward?

35 shocking stars who risked cheating on their bae with... this.
Star couples look like they have fairy-tale lives, but in private and away from the flashbulbs they still cheat on each other... all the time. The busted cheaters on the following pages not only cheated on their spouse, they cheated downward. Jesse James was the luckiest bro on the planet when he married Sandra Bullock, yet he cheated on her with a tatted beast named Michelle McGee. One Tree Hill star Chad Michael Murray had a beautiful wife, but he couldn't resist spending one night in Paris... Hilton, that is. Jay Z and Beyoncé are a hip-hop power couple, yet he stepped out on Queen Bey with a waitress/reality star. Arnold Schwarzenegger was married to Maria Shriver, JFK's niece, but he bedded his housekeeper and had a child with her. Then there's Hugh Grant, who famously got busted cheating on Elizabeth Hurley with a streetwalker. Other famous folks in this slideshow who cheated downward include Prince Charles, Eddie Murphy, Ethan Hawke, Gavin Rossdale, Charlie Sheen, Jude Law, Kobe Bryant and many more.

Did your favorite star get busted by cheating with someone who is not as hot? Find out!